<p>Tunnel seismic isolation is a novel seismic mitigation measure for tunnel structures. However, a deficiency in vulnerability analysis for seismic isolation of tunnels results in a lack of design guidelines. This study conducts a nonlinear incremental dynamic analysis utilizing a finite element numerical simulation, applying the reliability method to assess the seismic vulnerability of seismic isolated shield tunnels with respect to three types of representative surrounding ground. Then, the numerical analysis results are validated through shaking table tests employing the reaction displacement method, and a comparative analysis of the outcomes from both methods is presented. The findings indicate that the tunnel isolation layer has limited seismic isolation capabilities in silt, performs well in sand for low to moderate intensity earthquakes, and is highly effective in strongly weathered granite. Based on the vulnerability analysis outcomes, the influence of the seismic isolation layer on the tunnel’s seismic protection level is validated. The findings may serve as a reference for the seismic isolation design of shield tunnels.</p>